MOLECULAR CYTOGENETICS SHARED RESOURCE: PROJECT SUMMARY The Molecular Cytogenetics Shared Resource (MCSR) provides access to advanced DNA repair and genomic instability analyses to members of the Herbert Irving Comprehensive Cancer Center (HICCC). The services include (1) analyses of chromosomal structural, morphological, and rearrangement patterns (including karyotyping, spectral karyotyping (SKY), chromosome painting, and fluorescence in situ hybridization [FISH]), (2) analyses of genomic instability at specialized genomic regions (telomere, rDNA), (3) DNA damage responses and repair pathway analyses (including the kinetics of DNA repair protein foci), (4) development of genome-wide tools to analyze chromosomal translocation and mutations patterns (including high throughput sequence platforms), and (5) consultation and completed packages for experimental design, staining, data acquisition, and processing. Under the leadership of Shan Zha, PhD, an expert in DNA double-strand breaks repair, these comprehensive and customizable services, together with specialized instruments maintained by the MCSR, enable investigators at varying skill levels with the knowledge to characterize clonal changes as well as non- clonal genomic instability in cancer cells and in premalignant tissues from a wide range of organisms. Over the current project period (2014-2019), MSR has undergone leadership and instrument reorganization. In this process, the MCSR acquired new equipment and developed new assays, which significantly expanded its ability to quantitatively study DNA repair mechanisms. The reorganized MCSR is now managed by a dedicated PhD- level staff and provides convenient, cost-effective, and innovative service to HICCC members. The MCSR provides services that are not available from commercial sources and not easily accessible within the New York metropolitan area and are proven to be critically important to the research of many HICCC members, providing key preliminary data for grant applications and high-impact publications. In addition to providing both basic and advanced services across different area of DNA repair and genomic instability studies, the MCSR also provides training to HICCC members in the operation of specialized instruments and in sample preparation and analyses. In addition, consulting services are available to investigators to assist in the design of the most cost-effective analyses and provide controls needed to validate the assay and the data. The MCSR is committed to incorporating novel experimental portfolios and the use of analytic tools, providing state-of-the-art genomic stability services, and promoting accessibility of services through training and consulting in support of highly collaborative and innovative research ongoing at the HICCC. During the current project period, the MCSR was utilized by 21 HICCC members, supported key data for seven peer-reviewed publications, including four papers in high-impact journals (e.g., Nature, Molecular Cell), and currently supports research for five NIH-funded projects, four from NCI.